Jeremy Corbyn is predicted to win the Labour leadership by a huge margin(Getty)

The Labour Party has been forced to extend its deadline to sign-up to vote in its upcoming leadership election after it website crashed due to a surge of demand. The cut-off point to sign-up as a supporter and vote as to who will become the next leader of the party was originally meant to be 12pm on 12 August. However, many of those who tried to log on to parts of Labour's website were met with unresponsive web pages and 502 Bad Gateway messages.

Labour said sorry for the "technical issues" which left people frustrated at their inability to sign-up in time for the election vote. "Apologies if you experienced problems trying to join or register as a supporter this morning. Our site is working now," the party wrote on Twitter. The website was soon returning to a normal service following the last-minute rush to register and the party confirmed it has now extended its deadline to register to 3pm.

A spokesperson added: "This morning we understand that some people have had problems trying to join or register as a supporter of the Labour Party. We are extending the deadline to join or register and be able to vote in the leadership elections until 3pm.

"If you are experiencing problems with the website, you can also register as a supporter with a £3 text. Text SUPPORT to 78555 and wait for a further text tomorrow on how to complete registration."

In the last YouGov poll before the deadline to register passes, Jeremy Corbyn was predicted to storm the election after the survey predicted the left-wing Islington North MP would finish with a 32 point lead ahead of his nearest rival Andy Burnham.

Labour said since the general election defeat, some 70,000 people have paid their £3 to become registered supporters, giving them a vote if they "support the aims and values of the Labour Party".

Overall, there are around 282,000 party members eligible to vote, around 92,000 of which are trade unions members, with many of the biggest unions in the country already announcing their backing for Corbyn.

However, some 1,200 people have been banned from voting in the Labour leadership election because they are currently members of "rival" parties. These included 214 from the Green Party, 37 from the Trade Unionist and Socialist Coalition, 13 Tories, seven from Ukip as well as high-profile names such as journalist Toby Young and film director Ken Loach.